Topics of current studies include: 1) determination of glycine assimilation and canavanine sensitivity in the two varieties of Cryptococcus neoformans, 2) finding the reasons why most of C. neoformans var gattii isolated are avirulent for mice, 3) finding an effect of catecholamine concentrations of animal brain for the growth of C. neoformans and 4) taxonomic studies on the cerebral mycotic agents belonging to the genius Cladosporium. Biochemical study showed that 100% of C. neoformans var. gattii (B&C serotypes) utilize glycine as the sole source of carbon as well as nitrogen, while 19 and 11% of A and D serotypes, respectively, could utilize the amino acid. The glycine utilizing isolates were found to metabolize glycine via serine and pyruvate. One hundred per cent of C. neoformans var. gattii were also found to be resistant to L-canavanine up to 13 ml while 100% of serotype D and 30% of serotype A of C. neoformans rar. neoformans were sensitive to the drug. Protein and DNA synthesis were not affected by the drug in the resistant isolates while they were inhibited in the sensitive isolate. Rate of the drug uptake was the same in the two groups. Unlike C. neoformans var. neoformans, C. neoformans var. gattii spontaneously produced temperature sensitive, phenoloxidase negative subpopulations in a high proportion. These populations were avirulent for mice. The rats with catecholamines in brain permitted slower growth of C. neoformans than the control rats. The long lost Cladosporium bantianum was isolated from a cat lesion and was found to be significantly different from C. trichiodes. A new variety, Cladosporium trichiodes var. chlamydosporum isolated from a human brain abscess was described.